Pharyngeal reservoir drives gonorrhea epidemic in gay men

VIENNA – Venereologists are now convinced that the roaring epidemic of gonorrhea in men who have sex with men is driven mainly by pharyngeal infection, Colm O’Mahony, MD, said at the annual congress of the European Academy of Dermatology and Venereology.

“We think pharyngeal gonorrhea is now the most important factor in this continuing epidemic,” according to Dr. O’Mahony, professor of medicine and a venereologist at the University of Chester (England).

Recent studies have shown that men can carry Neisseria gonorrhoeae in their throats for weeks or months without symptoms and can readily spread the infection through unprotected oral sex.

Also, surveys of men who have sex with men (MSM) indicate that saliva is commonly used as a lubricant for anal sex. Australian investigators have estimated that about half of rectal gonorrhea in MSM would be eliminated if they stopped using their partner’s saliva for this purpose (Sex Trans Infect. 2016 Mar 3. pii:sextrans-2015-052502. doi: 10.1136/sextrans-2015-052502).

And then there is French kissing.

“Men don’t go out to a nightclub and have indiscriminate anal sex anymore. It’s not like that,” according to Dr. O’Mahony. “But they do kiss quite a lot of other men over the course of an evening, and it’s deep kissing. They may French kiss 15-20 other young men. And we think there’s actually a significant risk of transmission of gonorrhea from this simple deep kissing.”

Indeed, Australian investigators are now conducting a study examining whether having young gay men take a bottle of mouthwash with them when they go clubbing so they can take a good swish in between kissing will protect against N. gonorrhoeae infection.

“Apparently gonorrhea is quite sensitive to mouthwashes like Listerine. So we await those study results with interest,” he continued.

Dr. O’Mahony warned that the problem of multidrug-resistant gonorrhea is further along than most noninfectious disease experts realize. That’s a frightening prospect, given that an estimated 800,000 cases of gonorrhea occur annually in the United States alone. Because of well-documented treatment failures with cefixime and other oral cephalosporins, the Centers for Disease Control and Prevention now recommends only one regimen for the treatment of gonorrhea: dual treatment with a single intramuscular dose of 250 mg of ceftriaxone (Rocephin) plus 1 g of azithromycin in a single dose.

“There have already been some cases of ceftriaxone-resistant gonorrhea reported in Japan, Spain, and other parts of Europe. And we’re now seeing azithromycin-resistant gonorrhea throughout the U.K., which is a problem. So we are really worried that we will end up with untreatable gonorrhea within a couple of years,” Dr. O’Mahony said.

The evolving antimicrobial resistance scenario is reminiscent of the quinolone experience, he added.

“In 1992, I published the first reported case of quinolone-resistant gonorrhea in Liverpool. Five years later we had to stop using quinolones because more than 10% of gonorrhea was resistant,” the venereologist said.

In mid-2016 the CDC published the first-ever comprehensive data from its Gonococcal Isolate Surveillance Project. An analysis of more than 5,000 N. gonorrhoeae isolates obtained from men with gonococcal urethritis presenting at U.S. STD clinics showed that 25.3% of samples were resistant to tetracycline, 19.2% to ciprofloxacin, and 16.2% to penicillin. The prevalence of reduced azithromycin susceptibility jumped from 0.6% in 2013 to 2.5% in 2014. Reduced ceftriaxone susceptibility doubled from 0.4% in 2013 to 0.8% the following year. Antimicrobial susceptibility patterns varied by geographic region, with the highest rates of reduced susceptibility being seen in the Midwest and among MSM (MMWR Surveill Summ. 2016;65[No. SS-7]:1–19. doi: 10.15585/mmwr.ss6507a1).